It was like deja vu, a flashback to that all-too-familiar invasion of feathered-friends from Hitchcock’s thriller “The Birds.” The difference: this time, the attackers had four wings and six legs, and there were 200 million of them. A steady rustling noise like silk paper filled the air last week when a cloud of locusts swarmed over Fuerteventura and Lanzarote, two holiday-paradise islands of the Canaries.

“Locusts turn holiday into horror trip,” screamed the headline in Germany’s mass-circulation tabloid Bild. Strong winds had literally blown the 6-centimeter (2.5-inch) long animals over from Africa. Shocked vacationers barricaded their holiday apartments — hardly surprising, as they weren’t exactly in the mood to watch this miracle of nature.

Then again, few would have imagined that these ever-munching insects, Schistocerca gregaria in Latin, are normally very peaceful desert inhabitants. Tainted brown-beige, the locust in its solitary form resides in the deserts of Africa, living as a loner. But inside Dr. Jeckyl looms an ominous Mr. Hyde — and through a seemingly magical transformation, the insects morph into the orange and yellow colored vandals straight out of the Book of Revelations that are now invading Portugal’s coastline in masses in addition to the Canaries.

A continent under siege

Currently, Northern Africa is experiencing its worst locust plague in the last 15 years, and the ravenous pests are also holding a firm grip over Mauritania, Morocco and Algeria. Reminiscent of an image from the Old Testament, a huge swarm suddenly emerged in front of the pyramids of Gizeh in Egypt. In the bible, the Holy Land is spared from the locust plague, but this time they have landed in Israel, as well. Worse yet, an end to the plague is not in sight.

Last week, experts of the United Nations’ Food and Agriculture Organization (FAO) convened in Rome for a crisis meeting. Their bottom-line assessment was grim: The situation is even worse than they had feared and the plague could last several years, they said. The destruction of crops and famine could continue in Africa and hit other regions if these winged plant-killers aren’t stopped. “The next few months will be decisive in our fight against the plague,” said Keith Cressman of the FAO. “We’ll only have a chance if we can prevent another generation of animals from hatching in the spring.”

The first signs of a looming threat came back in autumn 2003. Rain in the Sahel Zone — usually a blessing for the population in this arid region — triggered a local mass-scale reproduction of the locusts or “hoppers,” as scientists call the young locusts when they are still unable to fly. Their number skyrockets when the conditions are favorable.

When the locust population becomes too big, and their food supply — in many cases farmers’ crops — becomes scant, a radical metamorphosis of the insects is set in motion. “Within a few hours, the crowding triggers a complete change in their behavior,” said zoologist Hans-Joerg Ferenz of the University of Halle-Wittenberg. The masses of insects instinctually begin a wide-ranging search for food. The young animals change their color over the course of a few weeks and a cataclysmic chain reaction is unleashed.

The FAO began issuing warnings about the problem early, and in February it requested $9 million in direct aid for insecticides and airplane and helicopter missions. In fact, quick and decisive action could have stopped the plague at that point. “If you intervene early, you have a good chance,” said Ferenz. After all, the insects start their feeding frenzy on foot, marching in troops several kilometers long. For five to six weeks, the masses of young locusts walz through the landscape eating everything in sight. They molt five times, and only then do they develop their wings.

From that point on, the plague can no longer be contained. Pure happenstance — the wind — determines which feeding grounds the adult animals will attack next. The swarms can cover up to 200 kilometers (120 miles) per day; and the ground troops, by this point, have literally turned into an air force.

If you manage to kill the locusts while they’re still grounded, this worst-case scenario can easily be prevented. “The donor countries just didn’t pay up soon enough,” said Cressman. The locusts, he said, have already reproduced at least twice since the FAO’s request for aid went out. Using their extendable rear, each female locust can deposit at least 80 eggs into the ground. If an entire swarm stops to deposit eggs into the ground, huge fields of eggs develop. And when the soil is moist, they develop very well. In fact, the insects’ number grows exponentially, and it becomes a terror without end.

Fighting back

In this fight, the playing field is not level to begin with. Farmers in Cairo, visibly helpless over the past few weeks, tried to drive the locusts away by burning tires. Digging up the fields where the insects had deposited their eggs — that is, if those fields can be spotted — is widely seen as the most promising conventional method to break the reproduction cycle. In the past, scientists used a type of fungus brew from the neem tree, an effective locust repellant. But in the end, the chemical sledgehammer was usually the only resort. In all, the countries affected by the plague have received a whopping 3 million liters of insecticides. The estimated costs for the mass-extermination have jumped to several hundred million dollars.

The battle may now be decided in Morocco and Algeria, and something like a final showdown appears to be nearing. The locusts have recently shown a preference for the valleys on the southern flanks of the Atlas mountains. “Currently, they are not sexually mature yet,” said Cressman, adding that it’s currently too cold in the region for the locusts to develop quickly. And that’s precisely the opportunity the mobile exterminators need: “If we can kill as many animals as possible now, then they won’t be able to lay eggs in the spring.”

The odds aren’t bad, and the Northern Africans are preparing for this battle meticulously. Using helicopters, they are trying to locate the swarms, which can consist of up to 10 billion insects. They even employ satellite-based systems in the hunt.

In all, some 9.6 million hectares (23.7 million acres) of land are set to be blanketed with insecticides next spring. The people of Northern Africa have accepted the poisoning of the environment because pesticides could cause less damage than the locusts. Failure is not an option.

“Things will be bad if the insects survive, reproduce and more rain falls before the spring,” said Cressman. Newly hatched locusts would then probably return to the Western Sahel. But danger is also looming in Saudi Arabia and Egypt, Cressman cautioned. “The winter rain on the Red Sea will also fuel the locusts’ dispersion down there.”

“The plague probably won’t end until the rain stops and the winds turn unfavorably for the locusts,” said zoologist Ferenz. The scientist gained experience dealing with locust plagues between 1987 and 1989. At that time, the winds carried the locusts so far they even reached England and the Caribbean.

Each time, unfavorable climate-related factors, not people, helped end the mass-scale locust reproduction, said Ferenz. “Humans have never been able to stop these catastrophes on their own,” he said.